The service-level agreement (SLA) refers to an agreement that is reached between both parties of a provider and a user in terms of quality and a level of a service, and represents a requirement on quality of service (QoS) from the perspective of the user. In a cloud computing scenario, as two core resources of a cloud, storage and computation are integrated and collaboratively provide various applications to the outside. To ensure QoS of a key application and predictability of various applications, a QoS mechanism needs to be introduced to schedule and manage storage resources.
Generally, in the prior art, storage resources are scheduled and managed in the following manners. A storage system and a computing system are independent of each other, and are managed separately, where the storage system provides a storage unit to the computing system for use, and manages the storage resources at the granularity of the storage unit. Furthermore, computing units, for example, virtual machines (VMs), in the computing system correspond to different storage units, where an SLA level is configured in advance for each VM according to QoS, and the storage system performs optimization and performance management on each storage unit according to the SLA level. However, in the prior art, resources can be processed and scheduled only between different storage units.